Devices for sending and receiving feedback information

ABSTRACT

An evolved Node B (eNB) for sending feedback information is described. The eNB includes a processor and instructions stored in memory that is in electronic communication with the processor. The eNB determines configuration parameters related to an Enhanced Physical Hybrid-Automatic Repeat reQuest (ARQ) Indicator Channel (EPHICH). The eNB also sends an uplink grant and an associated EPHICH resource indicator based on the configuration parameters. The eNB additionally receives data in a Physical Uplink Shared Channel (PUSCH). The eNB further sends Hybrid Automatic Repeat Request Acknowledgement/Negative Acknowledgement (HARQ-ACK) information based on the configuration parameters.

TECHNICAL FIELD

The present disclosure relates generally to communication systems. Morespecifically, the present disclosure relates to devices for sending andreceiving feedback information.

BACKGROUND

Wireless communication devices have become smaller and more powerful inorder to meet consumer needs and to improve portability and convenience.Consumers have become dependent upon wireless communication devices andhave come to expect reliable service, expanded areas of coverage andincreased functionality. A wireless communication system may providecommunication for a number of wireless communication devices, each ofwhich may be serviced by a base station. A base station may be a devicethat communicates with wireless communication devices.

As wireless communication devices have advanced, improvements incommunication capacity, speed, flexibility and efficiency have beensought. However, improving communication capacity, speed, flexibilityand efficiency may present certain problems.

For example, wireless communication devices may communicate with one ormore devices using a communication structure. However, the communicationstructure used may only offer limited flexibility and efficiency. Asillustrated by this discussion, systems and methods that improvecommunication flexibility and efficiency may be beneficial.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram illustrating one configuration of one or moreevolved Node Bs (eNBs) and one or more User Equipments (UEs) in whichsystems and methods for sending and receiving feedback information maybe implemented;

FIG. 2 is a flow diagram illustrating one implementation of a method forsending feedback information;

FIG. 3 is a flow diagram illustrating one implementation of a method forreceiving feedback information;

FIG. 4 is a flow diagram illustrating another implementation of a methodfor sending feedback information;

FIG. 5 is a flow diagram illustrating another implementation of a methodfor receiving feedback information;

FIG. 6 is a block diagram illustrating an example of Enhanced PhysicalHybrid-Automatic Repeat reQuest (ARQ) Indicator Channel (EPHICH) groupsets;

FIG. 7 is a block diagram illustrating one implementation of EPHICHgroup signaling;

FIG. 8 is a block diagram illustrating one implementation of signaling aTransmit Power Control (TPC) index, virtual cell ID (VCID) and EPHICHgroup set;

FIG. 9 is a block diagram illustrating another implementation ofsignaling a TPC index, VCID and EPHICH group set;

FIG. 10 is a block diagram illustrating yet another implementation ofsignaling a TPC index, VCID and EPHICH group set;

FIG. 11 is a block diagram illustrating one implementation of signalinga configuration set that may include at least one of a TPC index, VCIDand EPHICH group set;

FIG. 12 is a thread diagram illustrating one example of EPHICH resourcesignaling by an eNB and a UE;

FIG. 13 illustrates various components that may be utilized in a UE;

FIG. 14 illustrates various components that may be utilized in an eNB;

FIG. 15 is a block diagram illustrating one configuration of a UE inwhich systems and methods for sending feedback information may beimplemented; and

FIG. 16 is a block diagram illustrating one configuration of an eNB inwhich systems and methods for receiving feedback information may beimplemented.

DETAILED DESCRIPTION

An evolved Node B (eNB) for sending feedback information is described.The eNB includes a processor. The eNB also includes memory in electroniccommunication with the processor. Instructions stored in the memory areexecutable to determine configuration parameters related to an EnhancedPhysical Hybrid-Automatic Repeat reQuest (ARQ) Indicator Channel(EPHICH). The instructions are also executable to send an uplink grantand an associated EPHICH resource indicator based on the configurationparameters. The instructions are further executable to receive data in aPhysical Uplink Shared Channel (PUSCH). The instructions areadditionally executable to send Hybrid Automatic Repeat RequestAcknowledgement/Negative Acknowledgement (HARQ-ACK) information based onthe configuration parameters. The EPHICH resource indicator may includea field in downlink control information (DCI) corresponding to theuplink grant.

At least one of a virtual cell ID (VCID) and a transmit power control(TPC) index may be determined based on the EPHICH group set index. A TPCindex may be determined based on the EPHICH resource indicator. At leastone of a VCID and an EPHICH group set index may be determined based onthe TPC index. There may be multiple virtual cell IDs (VCIDs) configuredfor demodulation reference signals (DMRS). A single VCID for generatinga DMRS sequence may be determined based on the EPHICH resourceindicator.

The EPHICH resource indicator may include at least one of a physicalresource block (PRB) index and a cyclic shift index. The EPHICH groupindex may be determined based on at least one of the PRB index and thecyclic shift index. An EPHICH group set index may be determined based onthe EPHICH resource indicator. A configuration set index may bedetermined based on the EPHICH resource indicator.

A User Equipment (UE) for receiving feedback information is alsodescribed. The UE includes a processor and memory in electroniccommunication with the processor. Instructions stored in the memory areexecutable to receive an uplink grant and an associated EPHICH resourceindicator. The instructions are also executable to determineconfiguration parameters based on the EPHICH resource indicator. Theinstructions are further executable to send data in a PUSCH. Theinstructions are additionally executable to obtain HARQ-ACK informationbased on the configuration parameters.

An EPHICH group set index may be determined based on the EPHICH resourceindicator. At least one of a virtual cell ID (VCID) and a transmit powercontrol (TPC) index may be determined based on the EPHICH group setindex.

The EPHICH resource indicator may include a field in downlink controlinformation (DCI) corresponding to the uplink grant. An EPHICH groupindex may be determined based on the EPHICH resource indicator.

A method for sending feedback information by an eNB is also described.The method includes determining configuration parameters related to anEPHICH. The method also includes sending an uplink grant and anassociated EPHICH resource indicator based on the configurationparameters. The method further includes receiving data in a PUSCH. Themethod additionally includes sending HARQ-ACK information based on theconfiguration parameters.

A method for receiving feedback information by a UE is also described.The method includes receiving an uplink grant and an associated EPHICHresource indicator. The method also includes determining configurationparameters based on the EPHICH resource indicator. The method furtherincludes sending data in a Physical Uplink Shared Channel (PUSCH). Themethod additionally includes obtaining HARQ-ACK information based on theconfiguration parameters.

The 3rd Generation Partnership Project, also referred to as “3GPP,” is acollaboration agreement that aims to define globally applicabletechnical specifications and technical reports for third and fourthgeneration wireless communication systems. The 3GPP may definespecifications for next generation mobile networks, systems and devices.

3GPP Long Term Evolution (LTE) is the name given to a project to improvethe Universal Mobile Telecommunications System (UMTS) mobile phone ordevice standard to cope with future requirements. In one aspect, UMTShas been modified to provide support and specification for the EvolvedUniversal Terrestrial Radio Access (E-UTRA) and Evolved UniversalTerrestrial Radio Access Network (E-UTRAN).

At least some aspects of the systems and methods disclosed herein may bedescribed in relation to the 3GPP LTE, LTE-Advanced (LTE-A) and otherstandards (e.g., 3GPP Releases 8, 9, 10 and/or 11). However, the scopeof the present disclosure should not be limited in this regard. At leastsome aspects of the systems and methods disclosed herein may be utilizedin other types of wireless communication systems.

A wireless communication device may be an electronic device used tocommunicate voice and/or data to a base station, which in turn maycommunicate with a network of devices (e.g., public switched telephonenetwork (PSTN), the Internet, etc.). In describing systems and methodsherein, a wireless communication device may alternatively be referred toas a mobile station, a UE, an access terminal, a subscriber station, amobile terminal, a remote station, a user terminal, a terminal, asubscriber unit, a mobile device, etc. Examples of wirelesscommunication devices include cellular phones, smart phones, personaldigital assistants (PDAs), laptop computers, netbooks, e-readers,wireless modems, etc. In 3GPP specifications, a wireless communicationdevice is typically referred to as a UE. However, as the scope of thepresent disclosure should not be limited to the 3GPP standards, theterms “UE” and “wireless communication device” may be usedinterchangeably herein to mean the more general term “wirelesscommunication device.”

In 3GPP specifications, a base station is typically referred to as aNode B, an eNB, a home enhanced or evolved Node B (HeNB) or some othersimilar terminology. As the scope of the disclosure should not belimited to 3GPP standards, the terms “base station,” “Node B,” “eNB,”and “HeNB” may be used interchangeably herein to mean the more generalterm “base station.” Furthermore, one example of a “base station” is anaccess point. An access point may be an electronic device that providesaccess to a network (e.g., Local Area Network (LAN), the Internet, etc.)for wireless communication devices. The term “communication device” maybe used to denote both a wireless communication device and/or a basestation.

It should be noted that as used herein, a “cell” may be anycommunication channel that is specified by standardization or regulatorybodies to be used for International Mobile Telecommunications-Advanced(IMT-Advanced) and all of it or a subset of it may be adopted by 3GPP aslicensed bands (e.g., frequency bands) to be used for communicationbetween an eNB and a UE. “Configured cells” are those cells of which theUE is aware and is allowed by an eNB to transmit or receive information.“Configured cell(s)” may be serving cell(s). The UE may receive systeminformation and perform the required measurements on all configuredcells. “Activated cells” are those configured cells on which the UE istransmitting and receiving. That is, activated cells are those cells forwhich the UE monitors the physical downlink control channel (PDCCH) andin the case of a downlink transmission, those cells for which the UEdecodes a physical downlink shared channel (PDSCH). “Deactivated cells”are those configured cells that the UE is not monitoring thetransmission PDCCH. It should be noted that a “cell” may be described interms of differing dimensions. For example, a “cell” may have temporal,spatial (e.g., geographical) and frequency characteristics.

The systems and methods disclosed herein describe devices for sendingand receiving feedback information. This may be done in the context ofan Enhanced Physical Hybrid-Automatic Repeat reQuest (ARQ) IndicatorChannel (EPHICH). For example, physical uplink shared channel (PUSCH)Hybrid Automatic Repeat Request Acknowledgement/Negative Acknowledgement(HARQ-ACK) reporting on an EPHICH is described.

In Release 8-11 specifications of 3GPP, a Physical Hybrid-AutomaticRepeat reQuest (ARQ) Indicator Channel (PHICH) is used for transmissionof HARQ-ACK information to User Equipment (UE). By introducing a newcarrier type, the legacy control channels such as PHICH may not beavailable in future releases of 3GPP, such as Release 12 and beyond. Inthis disclosure, systems and methods to indicate to the UE the resourcesused for EPHICH are described.

One benefit of EPHICH for transmission of HARQ-ACK information is thatit may indicate to a UE whether the codewords sent from the UE arereceived at the eNB (e.g., base station, eNode B, etc.) correctly ornot. This indication may make adaptive transmission available to the UE.The use of EPHICH may also reduce the overhead of signaling in thedownlink by removing the need for transmission of an uplink grant as animplicit indication of a HARQ-ACK signal.

Various examples of the systems and methods disclosed herein are nowdescribed with reference to the Figures, where like reference numbersmay indicate functionally similar elements. The systems and methods asgenerally described and illustrated in the Figures herein could bearranged and designed in a wide variety of different implementations.Thus, the following more detailed description of severalimplementations, as represented in the Figures, is not intended to limitscope, as claimed, but is merely representative of the systems andmethods.

FIG. 1 is a block diagram illustrating one configuration of one or moreevolved Node Bs (eNBs) 160 and one or more User Equipments (UEs) 102 inwhich systems and methods for sending and receiving feedback informationmay be implemented. The one or more UEs 102 may communicate with one ormore eNBs 160 using one or more antennas 122 a-n. For example, a UE 102transmits electromagnetic signals to the eNB 160 and receiveselectromagnetic signals from the eNB 160 using the one or more antennas122 a-n. The eNB 160 communicates with the UE 102 using one or moreantennas 180 a-n.

The UE 102 and the eNB 160 may use one or more channels 119, 121 tocommunicate with each other. For example, a UE 102 may transmitinformation or data to the eNB 160 using one or more uplink channels121. Examples of uplink channels 121 include a physical uplink controlchannel (PUCCH) and a PUSCH, etc. The one or more eNBs 160 may alsotransmit information or data to the one or more UEs 102 using one ormore downlink channels 119, for instance. Examples of downlink channels119 include a PDCCH, a PDSCH, etc. Other kinds of channels may be used.For example, an EPHICH is a downlink channel 119 that may carry HARQ-ACKinformation corresponding to a PUSCH transmission.

The eNB 160 may include one or more transceivers 176, one or moredemodulators 172, one or more decoders 166, one or more encoders 109,one or more modulators 113, a data buffer 162 and an eNB operationsmodule 182. For example, one or more reception and/or transmission pathsmay be implemented in an eNB 160. For convenience, only a singletransceiver 176, decoder 166, demodulator 172, encoder 109 and modulator113 are illustrated in the eNB 160, though multiple parallel elements(e.g., transceivers 176, decoders 166, demodulators 172, encoders 109and modulators 113) may be implemented.

The transceiver 176 may include one or more receivers 178 and one ormore transmitters 117. The one or more receivers 178 may receive signalsfrom the UE 102 using one or more antennas 180 a-n. For example, thereceiver 178 may receive and downconvert signals to produce one or morereceived signals 174. The one or more received signals 174 may beprovided to a demodulator 172. The one or more transmitters 117 maytransmit signals to the UE 102 using one or more antennas 180 a-n. Forexample, the one or more transmitters 117 may upconvert and transmit oneor more modulated signals 115.

The demodulator 172 may demodulate the one or more received signals 174to produce one or more demodulated signals 170. The one or moredemodulated signals 170 may be provided to the decoder 166. The eNB 160may use the decoder 166 to decode signals. The decoder 166 may produceone or more decoded signals 164, 168. For example, a first eNB-decodedsignal 164 may comprise received payload data, which may be stored in adata buffer 162. A second eNB-decoded signal 168 may comprise overheaddata and/or control data. For example, the second eNB-decoded signal 168may provide data (e.g., PUSCH transmission data) that may be used by theeNB operations module 182 to perform one or more operations.

As used herein, the term “module” may mean that a particular element orcomponent may be implemented in hardware, software or a combination ofhardware and software. However, it should be noted that any elementdenoted as a “module” herein may alternatively be implemented inhardware. For example, the eNB operations module 182 may be implementedin hardware, software or a combination of both.

In general, the eNB operations module 182 may enable the eNB 160 tocommunicate with the one or more UEs 102. The eNB operations module 182may include one or more of configuration parameters 194, a configurationparameter determination module 196, a configuration signal determinationmodule 198 and an eNB HARQ-ACK generation module 125. In oneimplementation, the eNB operations module 182 may include aconfiguration signal 123. In another implementation, the eNB operationsmodule 182 may include an EPHICH resource indicator 107. In yet anotherimplementation, the eNB operations module 182 may include both aconfiguration signal 123 and an EPHICH resource indicator 107.

EPHICH time and/or frequency resources may be partitioned by the eNB 160in several non-overlapping groups. Through the systems and methodsdescribed herein, the eNB 160 may indicate (to the UE 102, for instance)the resources used for an EPHICH.

In one implementation, the configuration parameter determination module196 may determine configuration parameters 194 related to an EPHICH. Theconfiguration parameters 194 may include the resources used for anEPHICH. For example, the configuration parameters 194 may include thetime and/or frequency resources and/or scrambling sequence and/orspreading sequence related to an EPHICH. An EPHICH may carry HARQ-ACKinformation for a PUSCH transmission. Multiple EPHICHs may constitute anEPHICH group. For instance, multiple EPHICHs mapped to the same set ofresource elements may constitute an EPHICH group.

As used herein, a resource element is the smallest time and frequencyresource unit for uplink and/or downlink transmissions. A physicalchannel corresponds to a set of resource elements carrying informationoriginating from higher layers and is the interface between the eNB 160and the UE 102.

One or more EPHICH groups may be included in the configurationparameters 194. An EPHICH group may have an associated EPHICH groupindex that may be used (by the UE 102 and/or the eNB 160, for instance)to identify that particular EPHICH group.

EPHICH groups may be further associated with one or more EPHICH groupsets. The EPHICH group sets may be overlapping (e.g., multiple EPHICHgroup sets may include one or more of the same EPHICH groups). In oneimplementation, the configuration of EPHICH group sets may be cellspecific (e.g., all UEs 102 are informed about all or the same EPHICHgroup sets). In another implementation, the configuration of EPHICHgroup sets may be UE specific (e.g., UEs 102 may be configured withdifferent EPHICH group sets). In yet another implementation, theconfiguration of one or more EPHICH group sets may be cell specific andthe configuration of one or more other EPHICH group sets may be UEspecific. An EPHICH group set may have an associated EPHICH group setindex that may be used (by the UE 102 and/or the eNB 160, for instance)to identify that particular EPHICH group set. The configuration of theone or more EPHICH group sets may be performed by the configurationparameter determination module 196.

The configuration parameters 194 may additionally include Transmit PowerControl (TPC) parameters. The uplink transmit power may be determined bythe TPC (also referred to as a TPC loop). The TPC may be static,semi-static and/or dynamically varying (depending on the channel, forinstance). The TPC may depend on the long-term and short-term wirelesschannel between the UE 102 and the reception point (e.g., the eNB 160).The UE 102 may dynamically switch the reception point, and therefore theUE 102 may maintain multiple TPC sets (e.g., one TPC set for eachreception point). Dynamic switching between different TPC sets may bedone dynamically by transmission of a TPC index in a Downlink ControlInformation (DCI) field related to an uplink grant (e.g., DCI formats 0and 4 described below).

The downlink control information is sent in packets of pre-specifiedlength known as Downlink Control Information (DCI). A PDCCH may carry aDCI. DCIs may carry different information. For example, one DCI may beused to inform multiple UEs 102 about downlink resource allocation andanother may be used to inform a specific UE 102 about uplink resourceallocation, etc. Thus, depending on the functionality of a DCI,different DCIs with different functionality may have different lengths(e.g., bits). A DCI may transport downlink or uplink schedulinginformation and/or requests for aperiodic channel quality indicator(CQI) reports. It should be noted that a Cyclic Redundancy Check (CRC)may be scrambled based on a Radio Network Temporary Identifier (RNTI).In some configurations, functions such as a multicast control channel(MCCH) change and uplink power control commands for one cell and oneRNTI may not be included in the DCI but may be part of other downlinkcontrol information.

Different DCIs may be distinguished by the way they are formatted andcoded, which may be referred to as DCI formats. A DCI format is a set offields of DCI. For example, the DCI format 0 may be used for thescheduling of a PUSCH in one uplink (UL) cell. The DCI format 4 is usedfor the scheduling of a PUSCH in one UL cell with multi-antenna porttransmission mode.

The configuration parameters 194 may additionally include informationrelated to one or more demodulation reference signals (DMRS). A DMRS isa reference signal specific to a UE 102. A reference signal is apredefined sequence that is known to both transmitter and the receiver.The receiver, upon reception of the reference signal may perform channelestimation and extract information (e.g., channel state information(CSI), frequency shift, Doppler shift, delay spreading, etc.) that maybe used for one or more of demodulation of the accompanying dataperforming mobility measurement and CSI measurement. One of theparameters that may be used for generating the sequence of a referencesignal according to 3GPP specifications is a virtual cell ID (VCID). OneVCID may be used for generating a base sequence for DMRS for PUSCHtransmission, which also is referred to as a reference signal ID (RSID).For example, there may be multiple virtual cell IDs (VCIDs) configuredfor demodulation reference signals (DMRS). A single VCID for generatinga DMRS sequence may be determined based on the EPHICH resourceindicator. Another VCID may be used for generating a cyclic shift.

A cell ID (also referred to as a physical cell ID) may be obtained bythe UE 102 indirectly from synchronization signals at the time of cellsearch and synchronization. A VCID may be configured by the eNB 160 viaradio resource control (RRC) signaling and may replace the cell ID informulas in which the cell ID may be used (e.g., a formula related toderiving the DMRS sequence). One DMRS sequence may be referred to as thebase sequence. Several other DMRS sequences can be generated from thebase sequence by applying a cyclic shift of the base sequence. Eachsequence generated by the cyclic shift of the base sequence can bedetermined by a cyclic shift index. Therefore, the configurationparameters 194 may include a first VCID for generating the base sequencefor DMRS for a PUSCH transmission. For example, there may be multiplevirtual cell IDs (VCIDs) configured for demodulation reference signals(DMRS). A single VCID for generating a DMRS sequence may be determined(by the eNB 160 and/or the UE 102) based on the EPHICH resourceindicator. The configuration parameters 194 may also include a secondVCID for generating the cyclic shift and/or the cyclic shift index forDMRS for a PUSCH transmission.

The configuration parameter determination module 196 may configure oneor more sets of configurations for the UE 102. Each set ofconfigurations may include a combination of an EPHICH group set, anEPHICH group set index, an EPHICH group, an EPHICH group index, a firstVCID for generating the base sequence for DMRS for a PUSCH transmission,a second VCID for generating the cyclic shift for DMRS for a PUSCHtransmission, one or more TPC parameters and a TPC index.

In one implementation, the eNB 160 may indicate the configurationparameters 194 to the UE 102 by higher layer signaling. For example, theeNB 160 may send a configuration signal 123 to the UE 102 that mayinclude higher layer signaling (e.g., System Information (SI) signalingand/or RRC signaling). The configuration signal 123 may includeinformation elements that convey configuration parameters 194 (e.g. oneor more sets of configuration parameters). The configuration signal 123(and the associated information elements) may be broadcast ordedicatedly signaled. The configuration signal 123 may includeinformation elements that are cell specific or UE 102 specific.

The configuration signal 123 may also include an information elementthat indicates whether EPHICH time and/or frequency resources may beconfigured or not. In other words, the configuration signal 123 mayindicate whether EPHICH may be used in the downlink or not.

The configuration signal 123 may additionally include an informationelement that indicates at least one of an EPHICH group and an EPHICHgroup set. As discussed above, the EPHICH group may include multipleEPHICHs mapped to the same set of resource elements, and the EPHICHgroup set may include one or more EHPICH groups. The configurationsignal 123 may include one or more information elements that indicateone or more EPHICH group indexes. The configuration signal 123 may alsoinclude one or more information elements that indicate one or moreEPHICH group set indexes.

EPHICH resources may be identified similarly to PHICH resources asprovided by the following equations. For example, the equations providean approach for identifying EPHICH resources (e.g., time-frequencyresource elements). As described above, an EPHICH may carry theHARQ-ACK. Multiple EPHICHs mapped to the same set of resource elementsconstitute an EPHICH group, where EPHICHs within the same EPHICH groupmay be separated through different orthogonal sequences. An EPHICHresource may be identified by the index pair (n_(EPHICH) ^(group),n_(EPHICH) ^(seq)) where n_(EPHICH) ^(group) is the EPHICH group numberand n_(EPHICH) ^(seq) is the orthogonal sequence index within the group.

For a frame structure type 1, the number of EPHICH groups N_(EPHICH)^(group) is constant in all subframes and given by N_(EPHICH)^(group)=N_(g) (N_(RB) ^(DL)/8) for a normal cyclic prefix andN_(EPHICH) ^(group)=2·|N_(g)(N_(RB) ^(DL)/8)| for an extended cyclicprefix, where N_(g)ε{⅙,½,1,2} may be provided by higher layers (from theeNB 160, for instance). The index n_(EPHICH) ^(group) may range from 0to N_(EPHICH) ^(group)−1.

For a frame structure type 2, the number of EPHICH groups may varybetween downlink subframes and may be given by m_(i)·N_(EPHICH) ^(group)where m_(i) is given by Table 1 and N_(EPHICH) ^(group) by theexpression above. It should be noted that the frame structure type 2 isequivalent to time-division duplexing (TDD). The index n_(EPHICH)^(group) in a downlink subframe with non-zero EPHICH resources may rangefrom 0 to m_(i)·N_(EPHICH) ^(group)−1.

TABLE 1 The factor m_(i) for a frame structure type 2 UL-DL Subframenumber i configuration 0 1 2 3 4 5 6 7 8 9 0 2 1 — — — 2 1 — — — 1 0 1 —— 1 0 1 — — 1 2 0 0 — 1 0 0 0 — 1 0 3 1 0 — — — 0 0 0 1 1 4 0 0 — — 0 00 0 1 1 5 0 0 — 0 0 0 0 0 1 0 6 1 1 — — — 1 1 — — 1

For PUSCH transmissions scheduled from serving cell c in subframe n, aUE 102 may determine the corresponding EPHICH resource of serving cell cin subframe n+k_(EPHICH). For frequency-division duplexing (FDD),k_(EPHICH) is always 4. For a TDD scenario, if a UE 102 is configuredwith one serving cell, or if the UE 102 is configured with more than oneserving cell and the TDD uplink-downlink (UL-DL) configuration of allthe configured serving cells is the same, for PUSCH transmissionsscheduled from serving cell c in subframe n, a UE 102 may determine thecorresponding EPHICH resource of serving cell c in subframen+k_(EPHICH), where k_(EPHICH) is given in Table 2. In another TDDscenario, if a UE 102 is configured with more than one serving cell andthe TDD UL-DL configuration of at least two configured serving cells isnot the same, for PUSCH transmissions scheduled from serving cell c insubframe n, the UE 102 may determine the corresponding EPHICH resourceof serving cell c in subframe n+k_(EPHICH), where k_(EPHICH) is given inTable 2. For a subframe bundling operation, the corresponding EPHICHresource may be associated with the last subframe in the bundle.

TABLE 2 k_(EPHICH) for TDD TDD UL-DL subframe index n Configuration 0 12 3 4 5 6 7 8 9 0 4 7 6 4 7 6 1 4 6 4 6 2 6 6 3 6 6 6 4 6 6 5 6 6 4 6 64 7

The EPHICH resource may be identified by the index pair (n_(EPHICH)^(group),n_(EPHICH) ^(seq)) where n_(EPHICH) ^(group) is the EPHICHgroup number and n_(EPHICH) ^(seq) is the orthogonal sequence indexwithin the group and may be defined according to Equations (1) and (2).

n _(EPHICH) ^(group)=(I _(PRB) _(—) _(RA) +n _(DMRS))mod N _(EPHICH)^(group) +I _(EPHICH) N _(EPHICH) ^(group)  (1)

n _(EPHICH) ^(seq)=(└I _(PRB) _(—) _(RA) /N _(EPHICH) ^(group) ┘+n_(DMRS))mod 2N _(SF) ^(EPHICH)  (2)

In Equations (1) and (2), n_(DDMRS) may be mapped from the cyclic shiftfor DMRS field (according to Table 6) in the most recent PDCCH withuplink DCI format 4 for the transport block(s) associated with thecorresponding PUSCH transmission. n_(DMRS) may be set to zero, if thereis no PDCCH with uplink DCI format for the same transport block, and ifthe initial PUSCH for the same transport block is semi-persistentlyscheduled, or if the initial PUSCH for the same transport block isscheduled by the random access response grant. It should be noted thatthe EPHICH group may identify the EPHICH time and/or frequency resourcesand is different from the EPHICH resources.

N_(SF) ^(EPHICH) is the spreading factor size used for EPHICHmodulation. In particular, modulation may be performed in accordancewith 3GPP TS 36.211 as described hereafter. The block of bits b(0), . .. , b(M_(bit)−1) transmitted on one EPHICH in one subframe may bemodulated as described in Table 4 below (from Table 7.1.2-1 from 3GPP TS36.211, for example), resulting in a block of complex-valued modulationsymbols z(0), . . . , z(M_(s)−1), where M_(s)=M_(bit). In particular,Table 4 illustrates quadrature phase shift keying (QPSK) modulationmapping. In the case of QPSK modulation, pairs of bits, b(i), b(i+1) maybe mapped to complex-valued modulation symbols x=I+jQ according to Table4. Table 3 (from Table 6.9.1-1 from 3GPP TS 36.211, for example)specifies the modulation mappings or schemes applicable for the enhancedphysical hybrid ARQ indicator channel.

TABLE 3 Physical channel Modulation schemes EPHICH BPSK

TABLE 4 b(i), b(i + 1) I Q 00   1/{square root over (2)}   1/{squareroot over (2)} 01   1/{square root over (2)} −1/{square root over (2)}10 −1/{square root over (2)}   1/{square root over (2)} 11 −1/{squareroot over (2)} −1/{square root over (2)}The block of modulation symbols z(0), . . . , z(M_(s)−1) may besymbol-wise multiplied with an orthogonal sequence and scrambled,resulting in a sequence of modulation symbols d(0), . . . ,d(M_(symb)−1) according to

d(i) = w(i mod N_(SF)^(EPHICH)) ⋅ (1 − 2c(i)) ⋅ z(⌊i/N_(SF)^(EPHICH)⌋)where i = 0, …  , M_(symb) − 1 M_(symb) = N_(SF)^(EPHICH) ⋅ M_(s)$N_{SF}^{EPHICH} = \{ \begin{matrix}4 & {{normal}\mspace{14mu} {cyclic}\mspace{14mu} {prefix}} \\2 & {{extended}\mspace{14mu} {cyclic}\mspace{14mu} {prefix}}\end{matrix} $

and c(i) is a cell-specific scrambling sequence. The scrambling sequencegenerator may be initialized with c_(init)=(└n_(s)/2┘+1)·(2N_(ID)^(cell)+1)·2⁹+N_(ID) ^(cell) at the start of each subframe. The subframenumber is indicated by n_(s). The orthogonal sequences [w(0) . . .w(N_(SF) ^(EPHICH)−1)] for an EPHICH is given by Table 5 (from Table6.9.1-2 from 3GPP TS 36.211), where the sequence index n_(EPHICH) ^(seq)corresponds to the EPHICH number within the EPHICH group.

TABLE 5 Orthogonal sequence Sequence index Normal cyclic prefix Extendedcyclic prefix n_(EPHICH) ^(seq) N_(SF) ^(EPHICH) = 4 N_(SF) ^(EPHICH) =2 0 [+1 +1 +1 +1] [+1 +1] 1 [+1 −1 +1 −1] [+1 −1] 2 [+1 +1 −1 −1] [+j+j] 3 [+1 −1 −1 +1] [+j −j] 4 [+j +j +j +j] — 5 [+j −j +j −j] — 6 [+j +j−j −j] — 7 [+j −j −j +j] —

In effect, each bit of Ack/Nack to be transmitted on the EPHICH afterbinary phase shift keying (BPSK) modulation may be multiplied by anappropriate vector in Table 5 and as a result, the bit may be repeated 4times for normal cyclic prefix and repeated twice (considering thetransformation via the vector multiplication) for extended cyclicprefix.

I_(PRB) _(—) _(RA)=I_(PRB) _(—) _(RA) ^(lowest) ^(—) ^(index) for thefirst transport block of a PUSCH with associated PDCCH or for the caseof no associated PDCCH when the number of negatively acknowledgedtransport blocks is not equal to the number of transport blocksindicated in the most recent PDCCH associated with the correspondingPUSCH, or I_(PRB) _(—) _(RA)=I_(PRB) _(—) _(RA) ^(lowest) ^(—)^(index)+1 for a second transport block of a PUSCH with associatedPDCCH. I_(PRB) _(—) _(RA) ^(lowest) ^(—) ^(index) is the lowest physicalresource block (PRB) index in the first slot of the corresponding PUSCHtransmission. N_(EPHICH) ^(group) is the number of EPHICH groupsconfigured by higher layers as described above. I_(EPHICH)=1 for TDDUL-DL configuration with PUSCH transmission in subframe n=4 or 9, orI_(EPHICH)=0 otherwise.

TABLE 6 Cyclic Shift for DMRS Field in PDCCH with uplink DCI format in3GPP TS 36.212 n_(DMRS) 000 0 001 1 010 2 011 3 100 4 101 5 110 6 111 7

The configuration signal 123 may additionally include linkages betweenconfiguration parameters 194. For example, a linkage between items A andB represents a dependency between A and B. The dependency may havevarious forms. In one implementation, the value of B may be identifiedfrom a lookup table based on the value of A. In another implementation,the value of B may be identified from a formula that takes at least thevalue of A as an input parameter. In yet another implementation, aninformation element in which A is configured includes a parameter thattakes its value from the value of B that is stored in the informationelement in which B is configured.

One linkage that may be included in the configuration signal 123 may bebetween one EPHICH group set and one or more EPHICH groups or a list ofEPHICH groups. In other words, the configuration signal 123 may indicatea dependency between one EPHICH group set and one or more EPHICH groups.

Another linkage may be between an EPHICH group and an EPHICH group set.Yet another linkage may be between an EPHICH group set and a DMRSsetting (e.g., a first VCID for generating the base sequence for DMRSfor a PUSCH transmission and/or a second VCID for generating the cyclicshift for DMRS for a PUSCH transmission). Another linkage may be betweenan EPHICH group set and a TPC index. Yet another linkage may be betweena VCID (e.g., a DMRS setting) and a TPC index.

In some configurations, higher layer signaling, such as Radio ResourceControl (RRC) signaling, may configure whether the EPHICH is enabled ornot. For example, the eNB 160 may send RRC signaling to a UE 102 toconfigure an EPHICH. In one implementation, if an EPHICH is configured,the eNB 160 may send an EPHICH resource indicator 107 to one or more UEs102. The EPHICH resource indicator 107 may be used instead of or inaddition to the configuration signal 123. The eNB operations module 182may include an EPHICH resource indicator determination module 127. TheEPHICH resource indicator determination module 127 may generate theEPHICH resource indicator 107 based on the configuration parameters 194.In one implementation, the EPHICH resource indicator 107 may be a fieldin a DCI corresponding to an uplink grant. The uplink grant may be sentfrom the eNB 160 to the UE 102 to schedule a transmission on the uplinkchannel 121. The length of the field in the DCI may be, for example, oneto five bits (e.g., DCI bits). The DCI bits may be added to one or moreDCI formats for an uplink grant.

The DCI bits included in the EPHICH resource indicator 107 may be usedto indicate various resource parameters. In one implementation, the DCIbits may be used (by the UE 102, for instance) to determine an EPHICHgroup set index. Upon determining the EPHICH group set index, at leastone of a VCID and a TPC index may be determined based on the EPHICHgroup set index. The DCI bits may be used to determine either or both ofa first VCID for generating the base sequence for DMRS for a PUSCHtransmission and/or a second VCID for generating the cyclic shift forDMRS for a PUSCH transmission.

In another implementation, the DCI bits may be used to determine a TPCindex. Upon determining the TPC index, at least one of a VCID and anEPHICH group set index may be determined based on the TPC index. The TPCindex may be used to determine either or both of a first VCID forgenerating the base sequence for DMRS for a PUSCH transmission and/or asecond VCID for generating the cyclic shift for DMRS for a PUSCHtransmission.

In yet another implementation, the DCI bits may be used to determine oneor more VCIDs. The DCI bits may be used to determine either or both of afirst VCID for generating the base sequence for DMRS for a PUSCHtransmission and/or a second VCID for generating the cyclic shift forDMRS for a PUSCH transmission. Upon determining the one or more VCIDs,at least one of a TPC index and an EPHICH group set index may bedetermined based on the one or more VCIDs.

The DCI bits may also identify an EPHICH group index. Therefore, the DCIbits included in the EPHICH resource indicator 107 may indicate both theEPHICH group index and the EPHICH group set index. As described above,the EPHICH group index may be determined based on one or more of a PUSCHphysical resource block (PRB) number, a cyclic shift index for PUSCHDMRS and an nDMRS parameter (e.g., n_(DMRS) as described above).

The DCI bits may also identify a configuration set index. Aconfiguration set may include a combination of one EPHICH group set, oneTPC index and a VCID. Therefore, by indicating a configuration set, theDCI bits may indicate an associated EPHICH group set, TPC index and aVCID. The configuration set is discussed in more detail in connectionwith FIG. 11 below.

The eNB HARQ-ACK generation module 125 may generate HARQ-ACK informationbased on data received in a PUSCH transmission. For example, the eNB 160may receive data in a PUSCH transmission from the UE 102. The eNBHARQ-ACK generation module 125 may generate HARQ-ACK information basedon whether a signal (e.g., data) in the PUSCH was correctly received ornot. The eNB 160 may receive one or more codewords in a PUSCHtransmission from the UE 102. Therefore, the eNB HARQ-ACK generationmodule 125 may generate HARQ-ACK information corresponding to eachcodeword. The eNB HARQ-ACK generation module 125 may generate anAcknowledgement (ACK) bit for each packet that is correctly received ina PUSCH transmission. However, the eNB HARQ-ACK generation module 125may generate a Negative Acknowledgement (NACK) bit for each packet thatis not correctly received in a PUSCH transmission. In oneimplementation, the HARQ-ACK information may be transmitted on anEPHICH.

Upon determining the HARQ-ACK information, the eNB HARQ-ACK generationmodule 125 may send the HARQ-ACK information based on the configurationparameters 194. For example, the eNB HARQ-ACK generation module 125 maysend the HARQ-ACK information to the UE 102 using the resourcesindicated by the configuration signal 123 and/or the EPHICH resourceindicator 107. One or more EPHICHs may be sent to the UE 102corresponding to each codeword received in a PUSCH transmission from theUE 102. The one or more EPHICHs may be included in an EPHICH group. Theone or more EPHICH groups may be included in an EPHICH group set.

The configuration signal 123 and EPHICH resource indicator 107 may besent before an EPHICH transmission. For example, the eNB 160 may sendthe EPHICH resource indicator 107 with an uplink grant. At a later time,the eNB 160 may receive the PUSCH transmission based on the uplink grantand may send an EPHICH using the resources indicated by theconfiguration signal 123 and/or the EPHICH resource indicator 107.Therefore, the configuration signal 123 and/or the EPHICH resourceindicator 107 may be transmitted in advance of the transmission of theEPHICH.

The eNB operations module 182 may provide information 190 to the one ormore receivers 178. For example, the eNB operations module 182 mayinform the receiver(s) 178 when or when not to receive transmissionsbased on the configuration parameters 194.

The eNB operations module 182 may provide information 188 to thedemodulator 172. For example, the eNB operations module 182 may informthe demodulator 172 of a modulation pattern anticipated fortransmissions from the UE(s) 102.

The eNB operations module 182 may provide information 186 to the decoder166. For example, the eNB operations module 182 may inform the decoder166 of an anticipated encoding for transmissions from the UE(s) 102.

The eNB operations module 182 may provide information 101 to the encoder109. The information 101 may include data to be encoded and/orinstructions for encoding. For example, the eNB operations module 182may instruct the encoder 109 to encode transmission data 105 and/orother information 101. The other information 101 may include theconfiguration signal 123, the EPHICH resource indicator 107 and theHARQ-ACK information generated by the eNB HARQ-ACK generation module125.

The encoder 109 may encode transmission data 105 and/or otherinformation 101 provided by the eNB operations module 182. For example,encoding the data 105 and/or other information 101 may involve errordetection and/or correction coding, mapping data to space, time and/orfrequency resources for transmission, multiplexing, etc. The encoder 109may provide encoded data 111 to the modulator 113. The transmission data105 may include network data to be relayed to the UE 102.

The eNB operations module 182 may provide information 103 to themodulator 113. This information 103 may include instructions for themodulator 113. For example, the eNB operations module 182 may inform themodulator 113 of a modulation type (e.g., constellation mapping) to beused for transmissions to the UE(s) 102. The modulator 113 may modulatethe encoded data 111 to provide one or more modulated signals 115 to theone or more transmitters 117.

The eNB operations module 182 may provide information 192 to the one ormore transmitters 117. This information 192 may include instructions forthe one or more transmitters 117. For example, the eNB operations module182 may instruct the one or more transmitters 117 when to (or when notto) transmit a signal to the UE(s) 102. The one or more transmitters 117may upconvert and transmit the modulated signal(s) 115 to one or moreUEs 102.

Each of the one or more UEs 102 may include one or more transceivers118, one or more demodulators 114, one or more decoders 108, one or moreencoders 150, one or more modulators 154, a data buffer 104 and a UEoperations module 124. For example, one or more reception and/ortransmission paths may be implemented in the UE 102. For convenience,only a single transceiver 118, decoder 108, demodulator 114, encoder 150and modulator 154 are illustrated in the UE 102, though multipleparallel elements (e.g., transceivers 118, decoders 108, demodulators114, encoders 150 and modulators 154) may be implemented.

The transceiver 118 may include one or more receivers 120 and one ormore transmitters 158. The one or more receivers 120 may receive signalsfrom the eNB 160 using one or more antennas 122 a-n. For example, thereceiver 120 may receive and downconvert signals to produce one or morereceived signals 116. The one or more received signals 116 may beprovided to a demodulator 114. The one or more transmitters 158 maytransmit signals to the eNB 160 using one or more antennas 122 a-n. Forexample, the one or more transmitters 158 may upconvert and transmit oneor more modulated signals 156.

The demodulator 114 may demodulate the one or more received signals 116to produce one or more demodulated signals 112. The one or moredemodulated signals 112 may be provided to the decoder 108. The UE 102may use the decoder 108 to decode signals. The decoder 108 may produceone or more decoded signals 106, 110. For example, a first UE-decodedsignal 106 may comprise received payload data, which may be stored in adata buffer 104. A second UE-decoded signal 110 may comprise overheaddata and/or control data. For example, the second UE-decoded signal 110may provide data that may be used by the UE operations module 124 toperform one or more operations.

In general, the UE operations module 124 may enable the UE 102 tocommunicate with the one or more eNBs 160. The UE operations module 124may include one or more of configuration parameters 126, an interpretermodule 128 and a UE HARQ-ACK determination module 134. In oneimplementation, the UE operations module 124 may include a configurationsignal 130. In another implementation, the UE operations module 124 mayinclude an EPHICH resource indicator 132. In yet another implementation,the UE operations module 124 may include both a configuration signal 130and an EPHICH resource indicator 132.

In one implementation, the UE 102 may receive a configuration signal 130related to an EPHICH. The configuration signal 130 received by the UE102 may be the configuration signal 123 sent by the eNB 160. In anotherimplementation, the UE 102 may receive an EPHICH resource indicator 107.The EPHICH resource indicator 107 received by the UE 102 may be theEPHICH resource indicator 107 sent by the eNB 160. The EPHICH resourceindicator 107 may be associated with an uplink grant from the eNB 160.

The interpreter module 128 may determine configuration parameters 126based on the configuration signal 130 and/or the EPHICH resourceindicator 132. In one implementation, the interpreter module 128 maydetermine the configuration parameters 126 based only on theconfiguration signal 130. In another implementation, the interpretermodule 128 may determine the configuration parameters 126 based only onthe EPHICH resource indicator 132. In yet another implementation, theinterpreter module 128 may determine the configuration parameters 126based on a combination of the configuration signal 130 and the EPHICHresource indicator 132.

The configuration parameters 126 may indicate the resources used for anEPHICH. The configuration parameters 126 may be similar to theconfiguration parameters 194 determined by the eNB operations module182. For example, the configuration parameters 126 may include theinformation about the time and frequency resources related to an EPHICHdetermined by the eNB operations module 182. The configurationparameters 126 may include one or more EPHICH groups with associatedEPHICH group indexes. The configuration parameters 126 may also includeone or more EPHICH group sets with associated EPHICH group set indexes.Additionally, the configuration parameters 126 may include a first VCIDfor generating the base sequence for DMRS for a PUSCH transmission, asecond VCID for generating the cyclic shift for DMRS for a PUSCHtransmission, one or more TPC parameters and a TPC index as describedabove.

The UE 102 may send data in a PUSCH transmission. The UE 102 may sendthe data to the eNB 160 based on the uplink grant received from the eNB160. The UE 102 may include one or more codewords in the PUSCHtransmission that may be used by the eNB 160 for generating HARQ-ACKinformation. The HARQ-ACK information may be included in an EPHICH sentby the eNB 160 to the UE 102.

The UE HARQ-ACK determination module 134 may obtain HARQ-ACK informationbased on the configuration parameters 126. For example, theconfiguration parameters 126 may indicate the resources used for EPHICHtransmission. Using these resources, the UE 102 may receive one or moreEPHICHs. The UE HARQ-ACK determination module 134 may decode theinformation included in the one or more EPHICHs based on the resourcesthat are indicated in the configuration parameters 126 to obtain theHARQ-ACK information. The HARQ-ACK information may indicate whether thedata sent in the PUSCH transmission was successfully received by the eNB160 or not. If the HARQ-ACK information indicates that the data was notreceived by the eNB 160 (e.g., if the EPHICH is NACK), the UE 102 mayresend the data in a PUSCH transmission to the eNB 160.

The UE operations module 124 may provide information 148 to the one ormore receivers 120. For example, the UE operations module 124 may informthe receiver(s) 120 when or when not to receive transmissions based onthe uplink grant.

The UE operations module 124 may provide information 138 to thedemodulator 114. For example, the UE operations module 124 may informthe demodulator 114 of a modulation pattern anticipated fortransmissions from the eNB 160.

The UE operations module 124 may provide information 136 to the decoder108. For example, the UE operations module 124 may inform the decoder108 of an anticipated encoding for transmissions from the eNB 160.

The UE operations module 124 may provide information 142 to the encoder150. The information 142 may include data to be encoded and/orinstructions for encoding. For example, the UE operations module 124 mayinstruct the encoder 150 to encode transmission data 146 and/or otherinformation 142. The other information 142 may include the data to besent in a PUSCH transmission or retransmission in the event that theHARQ-ACK information indicates that the data transmission was notsuccessfully received by the eNB 160.

The encoder 150 may encode transmission data 146 and/or otherinformation 142 provided by the UE operations module 124. For example,encoding the data 146 and/or other information 142 may involve errordetection and/or correction coding, mapping data to space, time and/orfrequency resources for transmission, multiplexing, etc. The encoder 150may provide encoded data 152 to the modulator 154.

The UE operations module 124 may provide information 144 to themodulator 154. For example, the UE operations module 124 may inform themodulator 154 of a modulation type (e.g., constellation mapping) to beused for transmissions to the eNB 160. The modulator 154 may modulatethe encoded data 152 to provide one or more modulated signals 156 to theone or more transmitters 158.

The UE operations module 124 may provide information 140 to the one ormore transmitters 158. This information 140 may include instructions forthe one or more transmitters 158. For example, the UE operations module124 may instruct the one or more transmitters 158 when to transmit asignal to the eNB 160. The one or more transmitters 158 may upconvertand transmit the modulated signal(s) 156 to one or more eNBs 160.

It should be noted that one or more of the elements or parts thereofincluded in the eNB(s) 160 and UE(s) 102 may be implemented in hardware.For example, one or more of these elements or parts thereof may beimplemented as a chip, circuitry or hardware components, etc. It shouldalso be noted that one or more of the functions or methods describedherein may be implemented in and/or performed using hardware. Forexample, one or more of the methods described herein may be implementedin and/or realized using a chipset, an application-specific integratedcircuit (ASIC), a large-scale integrated circuit (LSI) or integratedcircuit, etc.

FIG. 2 is a flow diagram illustrating one implementation of a method 200for sending feedback information. An eNB 160 may determine 202configuration parameters 194 related to an EPHICH. For example, theconfiguration parameters 194 may indicate the resources (including acombination of time, frequency, spatial layer, code, scrambling orspreading sequence resources) used for an EPHICH. The configurationparameters 194 may include information about the time and frequencyresources related to an EPHICH. The configuration parameters 194 mayinclude one or more EPHICH groups with associated EPHICH group indexes.The configuration parameters 194 may also include one or more EPHICHgroup sets with associated EPHICH group set indexes. Additionally, theconfiguration parameters 194 may include a first VCID for generating thebase sequence for DMRS for a PUSCH transmission, a second VCID forgenerating the cyclic shift for DMRS for a PUSCH transmission, one ormore TPC parameters and a TPC index as described above in connectionwith FIG. 1.

The eNB 160 may send 204 a configuration signal 123 based on theconfiguration parameters 194. In one implementation, the configurationsignal 123 may include higher layer signaling (e.g., SI and/or RRCsignaling). The configuration signal 123 may convey the configurationparameters 194 to the UE 102. For example, the configuration signal 123may include an information element that indicates whether EPHICH timeand/or frequency resources may be configured or not. The configurationsignal 123 may also include an information element that indicates one ormore EPHICH groups and associated EPHICH group indexes. Theconfiguration signal 123 may additionally include one or moreinformation elements that indicate one or more EPHICH group sets andassociated EPHICH group set indexes. In some implementations, theconfiguration signal 123 may indicate that the EPHICH is configured.

The configuration signal 123 may additionally include linkages betweenconfiguration parameters 194. One linkage that may be included in theconfiguration signal 123 may be between one EPHICH group set and one ormore EPHICH groups or a list of EPHICH groups. Another linkage may bebetween an EPHICH group and an EPHICH group set. Another linkage may bebetween an EPHICH group set and a VCID (e.g., a first VCID forgenerating the base sequence for DMRS for a PUSCH transmission and/or asecond VCID for generating the cyclic shift for DMRS for a PUSCHtransmission). Another linkage may be between an EPHICH group set and aTPC index. Yet another linkage may be between a VCID (e.g., a DMRSsetting) and a TPC index.

The eNB 160 may receive 206 data in a PUSCH. The data may be received206 from a UE 102. The PUSCH transmission may be scheduled by the eNB160 through an uplink grant sent to the UE 102.

The eNB 160 may send 208 HARQ-ACK information based on the configurationparameters 194. For example, the eNB 160 may send 208 the HARQ-ACKinformation to the UE 102 using the resources indicated by theconfiguration signal 123. The HARQ-ACK information may be included in anEPHICH. One or more EPHICHs may be sent 208 to the UE 102 thatcorrespond to codeword(s) received in a PUSCH transmission from the UE102. The one or more EPHICHs may be included in an EPHICH group. The oneor more EPHICH groups may be included in an EPHICH group set.

FIG. 3 is a flow diagram illustrating one implementation of a method 300for receiving feedback information. A UE 102 may receive 302 aconfiguration signal 130 related to an EPHICH. For example, theconfiguration signal 130 received by the UE 102 may be sent by an eNB160. The configuration signal 130 may include higher layer signaling. Insome implementations, the configuration signal 123 may indicate that theEPHICH is configured.

The UE 102 may determine 304 configuration parameters 126 based on theconfiguration signal 130. The configuration parameters 126 may indicatethe resources used for an EPHICH. For example, the configurationparameters 126 may include information about the time and frequencyresources related to an EPHICH. The configuration parameters 126 mayinclude one or more EPHICH groups with associated EPHICH group indexes.The configuration parameters 126 may also include one or more EPHICHgroup sets with associated EPHICH group set indexes. Additionally, theconfiguration parameters 126 may include a first VCID for generating thebase sequence for DMRS for a PUSCH transmission, a second VCID forgenerating the cyclic shift for DMRS for a PUSCH transmission, one ormore TPC parameters and a TPC index as described above in connectionwith FIG. 1.

The UE 102 may send 306 data in a PUSCH. The UE 102 may send 306 thedata to the eNB 160 based on an uplink grant received from the eNB 160.The UE 102 may include one or more codewords in the PUSCH transmissionthat may be used by the eNB 160 for generating HARQ-ACK information. TheHARQ-ACK information may be included in an EPHICH sent by the eNB 160 tothe UE 102.

The UE 102 may obtain 308 HARQ-ACK information based on theconfiguration parameters 126. For example, the configuration parameters126 may indicate the resources used for the EPHICH transmission. Usingthese resources, the UE 102 may receive one or more EPHICHs. Therefore,the UE 102 may decode the information included in the one or moreEPHICHs based on the resources that are indicated in the configurationparameters 126 to obtain 308 the HARQ-ACK information. The HARQ-ACKinformation may indicate whether the data sent 306 in the PUSCHtransmission was successfully received by the eNB 160 or not. The UE 102may resend the data in a PUSCH transmission if the HARQ-ACK informationindicates that the data was not successfully received by the eNB 160.

FIG. 4 is a flow diagram illustrating another implementation of a method400 for sending feedback information. An eNB 160 may determine 402configuration parameters 194 related to an EPHICH. This may be done asdescribed above in connection with FIG. 2.

The eNB 160 may send 404 an uplink grant and an associated EPHICHresource indicator 107 based on the configuration parameters 194. Forexample, eNB 160 may generate the EPHICH resource indicator 107 based onthe configuration parameters 194. In one implementation, the EPHICHresource indicator 107 may be a field in a DCI corresponding to anuplink grant. The uplink grant may be sent 404 from the eNB 160 to theUE 102 to schedule a transmission on the uplink channel 121.

The EPHICH resource indicator 107 may convey the configurationparameters 194 to the UE 102. For example, the EPHICH resource indicator107 may indicate one or more EPHICH group and associated EPHICH groupindexes. The EPHICH resource indicator 107 may additionally indicate oneor more EPHICH group sets and associated EPHICH group set indexes. TheEPHICH group index may be indicated based on one or more of a PUSCHphysical resource block (PRB) number, a cyclic shift index for PUSCHDMRS and an nDMRS parameter.

The EPHICH resource indicator 107 may also indicate various dependenciesbetween resource parameters. In one implementation, the EPHICH resourceindicator 107 may indicate (to the UE 102, for instance) an EPHICH groupset index. At least one of a VCID and a TPC index may be determinedbased on a linkage to the EPHICH group set index. The EPHICH resourceindicator 107 may be used to determine either or both of a first VCIDfor generating the base sequence for DMRS for a PUSCH transmissionand/or a second VCID for generating the cyclic shift for DMRS for aPUSCH transmission.

In another implementation, the EPHICH resource indicator 107 mayindicate a TPC index. At least one of a VCID and an EPHICH group setindex may be determined based on a linkage to the TPC index. The TPCindex may be used to determine either or both of a first VCID forgenerating the base sequence for DMRS for a PUSCH transmission and/or asecond VCID for generating the cyclic shift for DMRS for a PUSCHtransmission.

In yet another implementation, the EPHICH resource indicator 107 mayindicate one or more VCIDs. The EPHICH resource indicator 107 mayindicate either or both of a first VCID for generating the base sequencefor DMRS for a PUSCH transmission and/or a second VCID for generatingthe cyclic shift for DMRS for a PUSCH transmission. At least one of aTPC index and an EPHICH group set index may be determined based on alinkage to the one or more VCIDs.

The EPHICH resource indicator 107 may also indicate a configuration set.A configuration set may include one EPHICH group set, one TPC index anda VCID. Therefore, by indicating a configuration set, the EPHICHresource indicator 107 may indicate an associated EPHICH group set, TPCindex and a VCID.

The eNB 160 may receive 406 data in a PUSCH. The data may be received406 from a UE 102. The PUSCH transmission may be scheduled by the eNB160 through an uplink grant sent to the UE 102.

The eNB 160 may send 408 HARQ-ACK information based on the configurationparameters 194. This may be done as described above in connection withFIG. 2.

FIG. 5 is a flow diagram illustrating another implementation of a method500 for receiving feedback information. A UE 102 may receive 502 anuplink grant and an associated EPHICH resource indicator 132. Forexample, the EPHICH resource indicator 132 may be generated (by an eNB160, for instance) as described above in connection with FIG. 4. In oneimplementation, the EPHICH resource indicator 132 may be a field in aDCI corresponding to the uplink grant. The uplink grant may be sent fromthe eNB 160 to the UE 102 to schedule a transmission on the uplinkchannel 121.

The UE 102 may determine 504 configuration parameters 126 based on theEPHICH resource indicator 132. The EPHICH resource indicator 132 mayconvey the configuration parameters 126 to the UE 102 as described abovein connection with FIG. 4.

The configuration parameters 126 may indicate the resources used for anEPHICH. The configuration parameters 126 may include information aboutthe time and frequency resources related to an EPHICH. For example, theconfiguration parameters 126 may include one or more EPHICH groups withassociated EPHICH group indexes. The configuration parameters 126 mayalso include one or more EPHICH group sets with associated EPHICH groupset indexes. Additionally, the configuration parameters 126 may includea first VCID for generating the base sequence for DMRS for a PUSCHtransmission, a second VCID for generating the cyclic shift for DMRS fora PUSCH transmission, one or more TPC parameters and a TPC index asdescribed above in connection with FIG. 1.

The UE 102 may send 506 data in a PUSCH. This may be accomplished asdescribed above in connection with FIG. 3.

The UE 102 may obtain 508 HARQ-ACK information based on theconfiguration parameters 126. This may be accomplished as describedabove in connection with FIG. 3.

FIG. 6 is a block diagram illustrating an example of EPHICH group sets.As described above in connection with FIG. 1, an EPHICH may carryHARQ-ACK information corresponding to a PUSCH transmission. MultipleEPHICHs constitute an EPHICH group. For example, multiple EPHICHs mappedto the same set of resource elements may constitute an EPHICH group.EPHICH time and/or frequency resources may be partitioned (by an eNB160) in several non-overlapping groups. EPHICH groups may be furtherassociated with one or more EPHICH group sets. The EPHICH group sets maybe overlapping (e.g., multiple EPHICH group sets may include one or moreof the same EPHICH groups).

The EPHICH group sets may utilize different EPHICH time and frequencyresources as depicted in FIG. 6. For example, an EPHICH group may beassociated with one or more resource sets 631 a-g. A resource set 631may include one or more resource elements (e.g., units of time-frequencyresources). The time and frequency resources may correspond to a radiosubframe. The subframe may span one millisecond. The time resources maybe divided into two slots 629.

In one example of an EPHICH group set, Set 1 includes three EPHICHgroups. Group 1 of Set 1 includes resource set A 631 a and resource setB 631 b. Resource set A 631 a is in the first slot 629 a and resourceset B 631 b is in the second slot 629 b. Group 1 of Set 1 isnon-contiguous. A non-contiguous group may be separated by one or moreresources elements and/or may be in different slots. For example, Group1 of Set 1 is non-contiguous since part of the resources is in the firstslot and part of it in the second slot and some resource elementsseparate the two groups. Group 3 of Set 1 is an example of a contiguousresource. Group 2 of Set 1 is associated with resource set C 631 c inthe second slot 629 b. Group 3 of Set 1 is associated with resource setD 631 d in the first slot 629 a. It should be noted that the EPHICHgroups of Set 1 may use different time and frequency resources, but areassociated with the same EPHICH group set 631.

In another example of an EPHICH group set, Set 2 includes two EPHICHgroups. Group 1 of Set 2 is associated with resource set E 631 e in thefirst time slot 629 a. Group 2 of Set 2 is associated with resource setF 631 f in the second slot 629 b. It should be noted that Group 1 of Set2 overlaps Group 1 of Set 1 (e.g., Set 1 and Set 2 overlap). In otherwords, resource set A 631 a overlaps resource set E 631 e. However,EPHICH groups in the same EPHICH group set may not overlap. Therefore,multiple EPHICH group sets may include one or more of the same EPHICHs.

In yet another example of an EPHICH group set, Set 3 includes one EPHICHgroup. Group 1 of Set 3 is associated with resource set G 631 g in thefirst slot 629 a. Set 3 illustrates that an EPHICH group set may includeone EPHICH group.

The EPHICH groups and EPHICH group sets may be indicated through acombination of configuration parameters 126, 194. This may beaccomplished as described above in connection with FIG. 1.

FIG. 7 is a block diagram illustrating one implementation of EPHICHgroup 739 signaling. In this implementation, four EPHICH groups 739 a-dmay each include eight EPHICHs 737. Multiple EPHICHs 737 may bemultiplexed in one EPHICH group 739 and each EPHICH 737 may use anEPHICH sequence that is orthogonal to the sequences used by otherEPHICHs 737 in the same EPHICH group 739. The EPHICH sequence may spreadthe EPHICH 737 over all or some of the time and/or frequency resourcesof an EPHICH group 739.

A particular EPHICH 737 may be indicated by an index pair that mayinclude an EPHICH sequence number 743 (e.g., the EPHICH sequence index)and an EPHICH group number 745 (e.g., the EPHICH group index). Differentcombinations of configuration parameters 741 a-b may indicate the EPHICHsequence number 743 and the EPHICH group number 745. For example, theEPHICH sequence number 743 and the EPHICH group number 745 may beindicated through different combinations of a PUSCH PRB number, cyclicshift of the DMRS and/or an nDMRS parameter. In one implementation, thelowest PRB index of the PUSCH may indicate the EPHICH group number 745.Other configuration parameters 741 may also be used to generate theEPHICH sequence number 743 and the EPHICH group number 745. In oneimplementation, the EPHICH groups 739 a-d may be indicated through acombination of configuration parameters 126, 194 as described above inconnection with FIG. 1.

In one implementation, the EPHICH sequence number 743 and an EPHICHgroup number 745 may be generated by an eNB 160. The EPHICH sequencenumber 743 and an EPHICH group number 745 may be signaled by sending aconfiguration signal 123 and/or an EPHICH resource indicator 107 to theUE 102.

FIG. 8 is a block diagram illustrating one implementation of signaling atransmit power control (TPC) index 847, VCID 849 and EPHICH group set851. In this implementation, a TPC index 847 may be signaled.Furthermore, a VCID 849 and an EPHICH group set 851 may be determinedbased on linkages 855, 857. For example, multiple TPC indexes 847 a-c,VCIDs 849 a-c and EPHICH group sets 851 a-c are configured. The VCIDs849 may be used for generating PUSCH DMRS as described above inconnection with FIG. 1. The EPHICH group set 851 may include one or moreEPHICHs 837 and one or more EPHICH groups 839.

The TPC indexes 847, VCIDs 849 and EPHICH group sets 851 may beassociated through linkages 855 a-c and 857 a-c. For example, the firstTPC index 847 a and the first VCID 849 a may be associated with a firstlinkage 855 a. The first VCID 849 a and the first EPHICH group set 851 amay be associated with a second linkage 857 a. In one implementation,the TPC indexes 847, VCIDs 849, EPHICH group sets 851 and linkages 855,857 may be indicated through a combination of configuration parameters126, 194 as described above in connection with FIG. 1.

In this implementation, a TPC index 847 may be indicated based onconfiguration parameters 841. The configuration parameters 841 may bedetermined by an eNB 160 and sent to a UE 102 via a configuration signal123, an EPHICH resource indicator 107 or a combination of theconfiguration signal 123 and EPHICH resource indicator 107. For example,the DCI bits of the EPHICH resource indicator 107 may dynamically selectthe TPS index 847.

Upon determining the indicated TPC index 847, the associated VCID 849and EPHICH group set 851 may be determined based on the linkages 855,857. For example, if the first TPC index 847 a is indicated by theconfiguration parameters 841, the first VCID 849 a is indicated by thefirst linkage 855 a and the first EPHICH group set 851 a is indicated bythe second linkage 857 a.

FIG. 9 is a block diagram illustrating another implementation ofsignaling a TPC index 947, VCID 949 and EPHICH group set 951. In thisimplementation, a VCID 949 may be signaled and a TPC index 947 and anEPHICH group set 951 may be determined based on linkages 955, 957. Forexample, multiple TPC indexes 947 a-c, VCIDs 949 a-c and EPHICH groupsets 951 a-c are configured. The EPHICH group set 951 may include one ormore EPHICHs 937 and one or more EPHICH groups 939.

The TPC indexes 947, VCIDs 949 and EPHICH group sets 951 may beassociated through linkages 955 a-c, 957 a-c. For example, the firstVCID 949 a and the first TPC index 947 a may be associated with a firstlinkage 955 a. The first VCID 949 a and the first EPHICH group set 951 amay be associated with a second linkage 957 a. In one implementation,the TPC indexes 947, VCIDs 949, EPHICH group sets 951 and linkages 955,957 may be indicated through a combination of configuration parameters126, 194 as described above in connection with FIG. 1.

In this implementation, a VCID 949 a may be indicated based onconfiguration parameters 941. The configuration parameters 941 may bedetermined by an eNB 160 and sent to a UE 102 via a configuration signal123, an EPHICH resource indicator 107 or a combination of theconfiguration signal 123 and EPHICH resource indicator 107. For example,the DCI bits of the EPHICH resource indicator 107 may dynamically selectthe VCID 949 a.

Upon determining the indicated VCID 949, the associated TPC index 947and EPHICH group set 951 may be determined based on the linkages 955,957. For example, if the first VCID 949 a is indicated by theconfiguration parameters 941, the first TPC index 947 a is indicated bythe first linkage 955 a and the first EPHICH group set 951 a isindicated by the second linkage 957 a.

FIG. 10 is a block diagram illustrating yet another implementation ofsignaling a TPC index 1047, VCID 1049 and EPHICH group set 1051. In thisimplementation, an EPHICH group set 1051 may be signaled and a TPC index1047 and a VCID 1049 may be determined based on linkages 1055, 1057. Forexample, multiple TPC indexes 1047 a-c, VCIDs 1049 a-c and EPHICH groupsets 1051 a-c are configured. The EPHICH group set 1051 may include oneor more EPHICHs 1037 and one or more EPHICH groups 1039.

The TPC indexes 1047, VCIDs 1049 and EPHICH group sets 1051 may beassociated through linkages 1055 a-c, 1057 a-c. For example, the firstVCID 1049 a and the first TPC index 1047 a may be associated with afirst linkage 1055 a. The first VCID 1049 a and the first EPHICH groupset 1051 a may be associated with a second linkage 1057 a. In oneimplementation, the TPC indexes 1047, VCIDs 1049, EPHICH group sets 1051and linkages 1055, 1057 may be indicated through a combination ofconfiguration parameters 126, 194 as described above in connection withFIG. 1.

In this implementation, an EPHICH group set 1051 may be indicated basedon configuration parameters 1041. The configuration parameters 1041 maybe determined by an eNB 160 and sent to a UE 102 via a configurationsignal 123, an EPHICH resource indicator 107 or a combination of theconfiguration signal 123 and EPHICH resource indicator 107. For example,the DCI bits of the EPHICH resource indicator 107 may dynamically selectthe EPHICH group set 1051.

Upon determining the indicated EPHICH group set 1051, the associatedVCID 1049 and TPC index 1047 may be determined based on the linkages1055, 1057. For example, if the first EPHICH group set 1051 a isindicated by the configuration parameters 1041, the first TPC index 1047a is indicated by the first linkage 1055 a and the first VCID 1049 a isindicated by the second linkage 1057 a.

FIG. 11 is a block diagram illustrating one implementation of signalinga configuration set 1153 that may include at least one of a TPC index1147, VCID 1149 and EPHICH group set 1151. In this implementation,multiple TPC indexes 1147 a-c, VCIDs 1149 a-c and EPHICH group sets 1151a-c are configured. An EPHICH group set 1151 may include one or moreEPHICHs 1137 and one or more EPHICH groups 1139. A TPC index 1147, VCID1149 and EPHICH group set 1151 may be associated with a configurationset 1153. In one implementation, the TPC indexes 1147, VCIDs 1149 andEPHICH group sets 1151 may be indicated through a combination ofconfiguration parameters 126, 194 as described above in connection withFIG. 1.

In this implementation, a configuration set 1153 may be indicated basedon configuration parameters 1141. The configuration parameters 1141 maybe determined by an eNB 160 and sent to a UE 102 via a configurationsignal 123, an EPHICH resource indicator 107 or a combination of theconfiguration signal 123 and EPHICH resource indicator 107. For example,the DCI bits of the EPHICH resource indicator 107 may dynamically selectthe configuration set 1153.

Upon determining the indicated configuration set 1153, the associatedTPC index 1147, VCID 1149 and EPHICH group set 1151 may be determined.For example, one of the configuration sets 1153 a-c may be signaled bythe configuration parameters 1141. If the first configuration set 1153 ais indicated by the configuration parameters 1141, the first TPC index1147 a, the first VCID 1149 a and the first EPHICH group set 1151 a arealso indicated based on their association with the first configurationset 1153 a.

FIG. 12 is a thread diagram illustrating one example of EPHICH resourcesignaling by an eNB 160 and a UE 102. The eNB 160 and the UE 102illustrated in FIG. 12 may be similar to the eNB 160 and UE 102described above in connection with FIG. 1. The eNB 160 may determine1202 configuration parameters 194 related to an EPHICH. This may be doneas described above in connection with FIG. 2. The eNB 160 may send 1204a configuration signal 123 to the UE 102 based on the configurationparameters 194. The configuration signal 123 may indicate theconfiguration of resources associated with at least one of an EPHICH, aVCID, a DMRS and a TPC.

The eNB 160 may also send 1206 an uplink grant and an associated EPHICHresource indicator 107 to the UE 102 based on the configurationparameters 194. This may be done as described above in connection withFIG. 4. The EPHICH resource indicator 107 may be sent 1206 at the sametime as the configuration signal 123 or the EPHICH resource indicator107 may be sent 1206 after the configuration signal 123.

Upon receiving the uplink grant and the associated EPHICH resourceindicator 132, the UE 102 may determine 1208 configuration parameters126 based on the EPHICH resource indicator 132. The configurationparameters 126 may indicate the resources used for an EPHICH. Theconfiguration parameters 126 may include information about the time andfrequency resources related to an EPHICH. For example, the configurationparameters 126 may include one or more EPHICH groups with associatedEPHICH group indexes. The configuration parameters 126 may also includeone or more EPHICH group sets with associated EPHICH group set indexes.Additionally, the configuration parameters 126 may include a first VCIDfor generating the base sequence for DMRS for a PUSCH transmission, asecond VCID for generating the cyclic shift for DMRS for a PUSCHtransmission, one or more TPC parameters and a TPC index as describedabove in connection with FIG. 1.

The UE 102 may send 1210 data in a PUSCH. The UE 102 may send 1210 thedata to the eNB 160 based on the uplink grant received from the eNB 160.For example, the UE 102 may include one or more codewords in the PUSCHtransmission that may be used by the eNB 160 for generating 1212HARQ-ACK information.

Upon receiving the PUSCH transmission from the UE 102, the eNB 160 maygenerate 1212 the HARQ-ACK information. For example, the eNB 160 maygenerate 1212 an acknowledgement (ACK) bit for each packet that iscorrectly received in the PUSCH transmission. However, the eNB 160 maygenerate 1212 a negative acknowledgement (NACK) bit for each packet thatis not correctly received in the PUSCH transmission.

Upon generating 1212 the HARQ-ACK information, the eNB 160 may send 1214the HARQ-ACK information based on the configuration parameters 194. Forexample, the eNB 160 may send 1214 the HARQ-ACK information to the UE102 using the resources indicated by the EPHICH resource indicator 107(and/or the configuration signal 123). The HARQ-ACK information may beincluded in an EPHICH. One or more EPHICHs may be sent 1214 to the UE102 corresponding to each codeword received in the PUSCH transmissionfrom the UE 102. The one or more EPHICHs may be included in an EPHICHgroup. The one or more EPHICH groups may be included in an EPHICH groupset.

Upon receiving the HARQ-ACK information from the eNB 160, the UE 102 mayobtain 1216 HARQ-ACK information based on the configuration parameters126. For example, the configuration parameters 126 may indicate theresources used for the EPHICH transmission. Using these resources, theUE 102 may receive one or more EPHICHs. The UE 102 may accordinglydecode the information included in the one or more EPHICHs based on theresources that are indicated in the configuration parameters 126 toobtain 1216 the HARQ-ACK information. The HARQ-ACK information mayindicate whether the data sent by the UE 102 in the PUSCH transmissionwas successfully received by the eNB 160 or not. The UE 102 may resend1218 the data in another PUSCH transmission if the HARQ-ACK informationindicates that the data was not successfully received by the eNB 160.

It should be noted that in the flow of messages depicted in FIG. 12,there may be at least k milliseconds roundtrip time. In an FDDconfiguration, k is normally four milliseconds. If the UE 102 receivesan uplink grant in subframe n, the UE 102 is scheduled to transmit PUSCHin subframe n+k. The eNB 160 may provide an EPHICH with HARQ-ACKinformation for the PUSCH transmission. If the UE 102 transmits multiplecodewords in the PUSCH transmission, multiple EPHICHs may be provided tothe UE 102. Once the UE 102 transmits PUSCH in subframe n+k, the UE 102monitors for an uplink grant and/or an EPHICH in subframe n+k+k.Therefore, the EPHICH resource indicator 107 (e.g., the DCIcorresponding to the uplink grant) may be sent 1206 in advance of thesending 1214 the EPHICH (with the HARQ-ACK information). FIG. 12 is oneexample of a UL transmission procedure, but there are several variationswhich are not shown.

FIG. 13 illustrates various components that may be utilized in a UE1302. The UE 1302 described in connection with FIG. 13 may beimplemented in accordance with the UE 102 described in connection withFIG. 1. The UE 1302 includes a processor 1363 that controls operation ofthe UE 1302. The processor 1363 may also be referred to as a centralprocessing unit (CPU). Memory 1369, which may include read-only memory(ROM), random access memory (RAM), a combination of the two or any typeof device that may store information, provides instructions 1365 a anddata 1367 a to the processor 1363. A portion of the memory 1369 may alsoinclude non-volatile random access memory (NVRAM). Instructions 1365 band data 1367 b may also reside in the processor 1363. Instructions 1365b and/or data 1367 b loaded into the processor 1363 may also includeinstructions 1365 a and/or data 1367 a from memory 1369 that were loadedfor execution or processing by the processor 1363. The instructions 1365b may be executed by the processor 1363 to implement one or more of themethods 300, 500 described above.

The UE 1302 may also include a housing that contains one or moretransmitters 1358 and one or more receivers 1320 to allow transmissionand reception of data. The transmitter(s) 1358 and receiver(s) 1320 maybe combined into one or more transceivers 1318. One or more antennas1322 a-n are attached to the housing and electrically coupled to thetransceiver 1318.

The various components of the UE 1302 are coupled together by a bussystem 1371, which may include a power bus, a control signal bus and astatus signal bus, in addition to a data bus. However, for the sake ofclarity, the various buses are illustrated in FIG. 13 as the bus system1371. The UE 1302 may also include a digital signal processor (DSP) 1373for use in processing signals. The UE 1302 may also include acommunications interface 1375 that provides user access to the functionsof the UE 1302. The UE 1302 illustrated in FIG. 13 is a functional blockdiagram rather than a listing of specific components.

FIG. 14 illustrates various components that may be utilized in an eNB1460. The eNB 1460 described in connection with FIG. 14 may beimplemented in accordance with the eNB 160 described in connection withFIG. 1. The eNB 1460 includes a processor 1477 that controls operationof the eNB 1460. The processor 1477 may also be referred to as a centralprocessing unit (CPU). Memory 1483, which may include read-only memory(ROM), random access memory (RAM), a combination of the two or any typeof device that may store information, provides instructions 1479 a anddata 1481 a to the processor 1477. A portion of the memory 1483 may alsoinclude non-volatile random access memory (NVRAM). Instructions 1479 band data 1481 b may also reside in the processor 1477. Instructions 1479b and/or data 1481 b loaded into the processor 1477 may also includeinstructions 1479 a and/or data 1481 a from memory 1483 that were loadedfor execution or processing by the processor 1477. The instructions 1479b may be executed by the processor 1477 to implement one or more of themethods 200, 400 described above.

The eNB 1460 may also include a housing that contains one or moretransmitters 1417 and one or more receivers 1478 to allow transmissionand reception of data. The transmitter(s) 1417 and receiver(s) 1478 maybe combined into one or more transceivers 1476. One or more antennas1480 a-n are attached to the housing and electrically coupled to thetransceiver 1476.

The various components of the eNB 1460 are coupled together by a bussystem 1485, which may include a power bus, a control signal bus and astatus signal bus, in addition to a data bus. However, for the sake ofclarity, the various buses are illustrated in FIG. 14 as the bus system1485. The eNB 1460 may also include a digital signal processor (DSP)1487 for use in processing signals. The eNB 1460 may also include acommunications interface 1489 that provides user access to the functionsof the eNB 1460. The eNB 1460 illustrated in FIG. 14 is a functionalblock diagram rather than a listing of specific components.

FIG. 15 is a block diagram illustrating one configuration of a UE 1502in which systems and methods for sending feedback information may beimplemented. The UE 1502 includes transmit means 1558, receive means1520 and control means 1524. The transmit means 1558, receive means 1520and control means 1524 may be configured to perform one or more of thefunctions described in connection with FIG. 3 and FIG. 13 above. FIG. 13above illustrates one example of a concrete apparatus structure of FIG.15. Other various structures may be implemented to realize one or moreof the functions of FIG. 3, FIG. 5 and FIG. 13. For example, a DSP maybe realized by software.

FIG. 16 is a block diagram illustrating one configuration of an eNB 1660in which systems and methods for receiving feedback information may beimplemented. The eNB 1660 includes transmit means 1617, receive means1678 and control means 1682. The transmit means 1617, receive means 1678and control means 1682 may be configured to perform one or more of thefunctions described in connection with FIG. 2 FIG. 14 above. FIG. 14above illustrates one example of a concrete apparatus structure of FIG.16. Other various structures may be implemented to realize one or moreof the functions of FIG. 2, FIG. 4 and FIG. 14. For example, a DSP maybe realized by software.

The term “computer-readable medium” refers to any available medium thatcan be accessed by a computer or a processor. The term“computer-readable medium,” as used herein, may denote a computer-and/or processor-readable medium that is non-transitory and tangible. Byway of example, and not limitation, a computer-readable orprocessor-readable medium may comprise RAM, ROM, EEPROM, CD-ROM or otheroptical disk storage, magnetic disk storage or other magnetic storagedevices, or any other medium that can be used to carry or store desiredprogram code in the form of instructions or data structures and that canbe accessed by a computer or processor. Disk and disc, as used herein,includes compact disc (CD), laser disc, optical disc, digital versatiledisc (DVD), floppy disk and Blu-ray® disc where disks usually reproducedata magnetically, while discs reproduce data optically with lasers.

It should be noted that one or more of the methods described herein maybe implemented in and/or performed using hardware. For example, one ormore of the methods described herein may be implemented in and/orrealized using a chipset, an application-specific integrated circuit(ASIC), a large-scale integrated circuit (LSI) or integrated circuit,etc.

Each of the methods disclosed herein comprises one or more steps oractions for achieving the described method. The method steps and/oractions may be interchanged with one another and/or combined into asingle step without departing from the scope of the claims. In otherwords, unless a specific order of steps or actions is required forproper operation of the method that is being described, the order and/oruse of specific steps and/or actions may be modified without departingfrom the scope of the claims.

It is to be understood that the claims are not limited to the preciseconfiguration and components illustrated above. Various modifications,changes and variations may be made in the arrangement, operation anddetails of the systems, methods and apparatus described herein withoutdeparting from the scope of the claims.

What is claimed is:
 1. An evolved Node B (eNB) for sending feedbackinformation, comprising: a processor; memory in electronic communicationwith the processor, wherein instructions stored in the memory areexecutable to: determine configuration parameters related to an EnhancedPhysical Hybrid-Automatic Repeat reQuest (ARQ) Indicator Channel(EPHICH); send an uplink grant and an associated EPHICH resourceindicator based on the configuration parameters; receive data in aPhysical Uplink Shared Channel (PUSCH); and send Hybrid Automatic RepeatRequest Acknowledgement/Negative Acknowledgement (HARQ-ACK) informationbased on the configuration parameters.
 2. The eNB of claim 1, whereinthe EPHICH resource indicator comprises a field in downlink controlinformation (DCI) corresponding to the uplink grant.
 3. The eNB of claim1, wherein an EPHICH group set index is determined based on the EPHICHresource indicator.
 4. The eNB of claim 3, wherein at least one of avirtual cell ID (VCID) and a transmit power control (TPC) index aredetermined based on the EPHICH group set index.
 5. The eNB of claim 1,wherein a transmit power control (TPC) index is determined based on theEPHICH resource indicator.
 6. The eNB of claim 5, wherein at least oneof a virtual cell ID (VCID) and an EPHICH group set index are determinedbased on the TPC index.
 7. The eNB of claim 1, wherein there aremultiple virtual cell IDs (VCIDs) configured for demodulation referencesignals (DMRS), and wherein a single VCID for generating a DMRS sequenceis determined based on the EPHICH resource indicator.
 8. The eNB ofclaim 7, wherein at least one of a transmit power control (TPC) indexand an EPHICH group set index are determined based on the virtual cellID (VCID).
 9. The eNB of claim 1, wherein an EPHICH group index isdetermined based on the EPHICH resource indicator.
 10. The eNB of claim9, wherein the EPHICH resource indicator comprises at least one of aphysical resource block (PRB) index and a cyclic shift index, andwherein the EPHICH group index is determined based on at least one ofthe PRB index and the cyclic shift index.
 11. The eNB of claim 10,wherein a configuration set index is determined based on the EPHICHresource indicator.
 12. A User Equipment (UE) for receiving feedbackinformation, comprising: a processor; memory in electronic communicationwith the processor, wherein instructions stored in the memory areexecutable to: receive an uplink grant and an associated EnhancedPhysical Hybrid-Automatic Repeat reQuest (ARQ) Indicator Channel(EPHICH) resource indicator; determine configuration parameters based onthe EPHICH resource indicator; send data in a Physical Uplink SharedChannel (PUSCH); and obtain Hybrid Automatic Repeat RequestAcknowledgement/Negative Acknowledgement (HARQ-ACK) information based onthe configuration parameters.
 13. The UE of claim 12, wherein the EPHICHresource indicator comprises a field in downlink control information(DCI) corresponding to the uplink grant.
 14. The UE of claim 12, whereinan EPHICH group set index is determined based on the EPHICH resourceindicator, and wherein at least one of a virtual cell ID (VCID) and atransmit power control (TPC) index are determined based on the EPHICHgroup set index.
 15. The UE of claim 12, wherein an EPHICH group indexis determined based on the EPHICH resource indicator.
 16. A method forsending feedback information by an evolved Node B (eNB), comprising:determining configuration parameters related to an Enhanced PhysicalHybrid-Automatic Repeat reQuest (ARQ) Indicator Channel (EPHICH);sending an uplink grant and an associated EPHICH resource indicatorbased on the configuration parameters; receiving data in a PhysicalUplink Shared Channel (PUSCH); and sending Hybrid Automatic RepeatRequest Acknowledgement/Negative Acknowledgement (HARQ-ACK) informationbased on the configuration parameters.
 17. The method of claim 16,wherein the EPHICH resource indicator comprises a field in downlinkcontrol information (DCI) corresponding to the uplink grant.
 18. Themethod of claim 16, wherein an EPHICH group set index is determinedbased on the EPHICH resource indicator.
 19. The method of claim 18,wherein at least one of a virtual cell ID (VCID) and a transmit powercontrol (TPC) index are determined based on the EPHICH group set index.20. The method of claim 16, wherein a transmit power control (TPC) indexis determined based on the EPHICH resource indicator.
 21. The method ofclaim 20, wherein at least one of a virtual cell ID (VCID) and an EPHICHgroup set index are determined based on the TPC index.
 22. The method ofclaim 16, wherein there are multiple virtual cell IDs (VCIDs) configuredfor demodulation reference signals (DMRS), and wherein a single VCID forgenerating a DMRS sequence is determined based on the EPHICH resourceindicator.
 23. The method of claim 22, wherein at least one of atransmit power control (TPC) index and an EPHICH group set index aredetermined based on the VCID.
 24. The method of claim 16, wherein anEPHICH group index is determined based on the EPHICH resource indicator.25. The method of claim 24, wherein the EPHICH resource indicatorcomprises at least one of a physical resource block (PRB) index and acyclic shift index, and wherein the EPHICH group index is determinedbased on at least one of the PRB index and the cyclic shift index. 26.The method of claim 25, wherein a configuration set index is determinedbased on the EPHICH resource indicator.
 27. A method for receivingfeedback information by a User Equipment (UE), comprising: receiving anuplink grant and an associated Enhanced Physical Hybrid-Automatic RepeatreQuest (ARQ) Indicator Channel (EPHICH) resource indicator; determiningconfiguration parameters based on the EPHICH resource indicator; sendingdata in a Physical Uplink Shared Channel (PUSCH); and obtaining HybridAutomatic Repeat Request Acknowledgement/Negative Acknowledgement(HARQ-ACK) information based on the configuration parameters.
 28. Themethod of claim 27, wherein the EPHICH resource indicator comprises afield in downlink control information (DCI) corresponding to the uplinkgrant.
 29. The method of claim 27, wherein an EPHICH group set index isdetermined based on the EPHICH resource indicator, and wherein at leastone of a virtual cell ID (VCID) and a transmit power control (TPC) indexare determined based on the EPHICH group set index.
 30. The method ofclaim 27, wherein an EPHICH group index is determined based on theEPHICH resource indicator.